The ear is our most important organ of communication, but hardly anyone thinks consciously about their ears. Yet they are high-performance precision instruments. When likened to a pair of scales, their possible measuring range is from 1 milligram to 1000 tons! But this organ was not designed for our loud civilization. The main problem is that once an individual's hearing is damaged, it is usually irreparable.
Apart from the pure facts and information we gather through our hearing, we also detect emotion behind a message gaining the ability to react appropriately. The perceived movement of the lips is normally insufficient for complete understanding of a message.
Our sense of hearing alerts us. Warning cries, an approaching car, the ringing of the telephone, a siren or a call from a doctor: everything passes through the ear. Good hearing helps us in spatial orientation. From the volume and time differences of the signals arriving at our two ears we can perceive the direction a noise is coming.
How does hearing protection work? Basically there are two types of hearing protectors:
Passive Ear Muffs - These dampen the sound, which means that all noises are reduced as they pass through the ear muffs. It is important that the hearing protection used provides enough attenuation to protect the hearing, but it is also important that it doesn't give attenuation so high that you are over protected. Overprotection can prevent you from hearing your co-workers, alarms and other important signals. The recommended sound level under the hearing protector is between 70 & 80 dB.
Active [Electronic] Ear Muffs - These have a built-in electronic circuit limit noise, but let you hold normal conversations with other people without having to remove your hearing protector. Built-in level dependent amplification amplifies speech and other harmless sounds while protecting against harmful sound levels. To prevent harmful noise levels, the internal speaker output is limited to 82 dB.
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